The value of suppressor effects in explicating the construct validity of symptom measures.

ABSTRACT: Suppressor effects are operating when the addition of a predictor increases the predictive power of another variable. We argue that suppressor effects can play a valuable role in explicating the construct validity of symptom measures by bringing into clearer focus opposing elements that are inherent--but largely hidden--in the measure's overall score. We illustrate this point using theoretically grounded, replicated suppressor effects that have emerged in analyses of the original Inventory of Depression and Anxiety Symptoms (IDAS; Watson et al., 2007) and its expanded 2nd version (IDAS-II; Watson et al., 2012). In Study 1, we demonstrate that the IDAS-II Appetite Gain and Appetite Loss scales contain both (a) a shared distress component that creates a positive correlation between them and

SUBMITTER: Watson D 

PROVIDER: S-EPMC3780394 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature